Synthetic polymers: A global threat to aquatic benthic environments.

Finding time-efficient and cost-effective data collection methods is a challenge when addressing aquatic litter pollution on a global scale. In this study, we analysed data on aquatic benthic debris collected worldwide by volunteer scuba divers through the Dive Against Debris® citizen science initiative, examining its relationship with spatial and socio-economic factors. Plastic-dominated litter was found in both marine (64 %) and freshwater (48 %) environments, followed by metal and glass.

Exploring different stroke populations' information needs: a cross-sectional study in England.

Background: While tailored information might have the potential to motivate stroke survivors to make essential lifestyle changes and improve long-term outcomes, how this varies among different stroke populations is not yet fully understood.

Method: From November 2022 to May 2023, stroke survivors in the UK, who were clinically stable, participated in a community-based, descriptive cross-sectional study. Participants rated several information themes on a Likert scale from one to five, indicating the relevance of each information group to them.

The Rhodium Analogue of Coenzyme B as an Anti-Photoregulatory Ligand Inhibiting Bacterial CarH Photoreceptors.

Coenzyme B (AdoCbl; 5'-deoxy-5'-adenosylcobalamin), the quintessential biological organometallic radical catalyst, has a formerly unanticipated, yet extensive, role in photoregulation in bacteria. The light-responsive cobalt-corrin AdoCbl performs this nonenzymatic role by facilitating the assembly of CarH photoreceptors into DNA-binding tetramers in the dark, suppressing gene expression. Conversely, exposure to light triggers the decomposition of this AdoCbl-bound complex by a still elusive photochemical mechanism, activating gene expression.

Citizen science through a recreational underwater diving project supports the collection of large-scale marine litter data: The Oceania case study.

In recent years, a growing body of literature on seafloor macro-litter has been produced worldwide. However, the spatial coverage of these studies is still limited and highly unbalanced, resulting in considerable knowledge gaps in some regions. To address this lack of information in Oceania, we extracted data from the Citizen Science project Dive Against Debris® to characterize marine debris collected by volunteer scuba divers on the coastal seafloor.

Two Distinct Thermodynamic Gradients for Cellular Metalation of Vitamin B.

The acquisition of Co by the corrin component of vitamin B follows one of two distinct pathways, referred to as early or late Co insertion. The late insertion pathway exploits a Co metallochaperone (CobW) from the COG0523 family of G3E GTPases, while the early insertion pathway does not. This provides an opportunity to contrast the thermodynamics of metalation in a metallochaperone-requiring and a metallochaperone-independent pathway.

Nutrient smuggling: Commensal gut bacteria-derived extracellular vesicles scavenge vitamin B12 and related cobamides for microbe and host acquisition.

The processes by which bacteria proactively scavenge essential nutrients in crowded environments such as the gastrointestinal tract are not fully understood. In this context, we observed that bacterial extracellular vesicles (BEVs) produced by the human commensal gut microbe contain multiple high-affinity vitamin B binding proteins suggesting that the vesicles play a role in micronutrient scavenging. Vitamin B belongs to the cobamide family of cofactors that regulate microbial communities through their limited bioavailability.

'It's like being pushed into sea on a boat with no oars': Breast cancer survivorship and rehabilitation support in Ireland and the UK.

Background: Cancer survivorship is associated with co-morbidities including anxiety, depression and cardiovascular disease (CVD). Rehabilitative care post-treatment is vital for survivors' psychological and physical well-being. The present study aimed to investigate breast cancer survivors' attitudes towards their health post-treatment; their awareness of co-morbidities associated with treatment; and their awareness of support systems available.

Exploring the onset of B -based mutualisms using a recently evolved Chlamydomonas auxotroph and B -producing bacteria.

Cobalamin (vitamin B ) is a cofactor for essential metabolic reactions in multiple eukaryotic taxa, including major primary producers such as algae, and yet only prokaryotes can produce it. Many bacteria can colonize the algal phycosphere, forming stable communities that gain preferential access to photosynthate and in return provide compounds such as B . Extended coexistence can then drive gene loss, leading to greater algal-bacterial interdependence.

Biosynthesis of cobamides: Methods for the detection, analysis and production of cobamides and biosynthetic intermediates.

Vitamin B, cobalamin, belongs to the broader cobamide family whose members are characterized by the presence of a cobalt-containing corrinoid ring. The ability to detect, isolate and characterize cobamides and their biosynthetic intermediates is an important prerequisite when attempting to study the synthesis of this remarkable group of compounds that play diverse roles across the three kingdoms of life. The synthesis of cobamides is restricted to only certain prokaryotes and their structural complexity entails an equally complex synthesis orchestrated through a multi-step biochemical pathway.

hydroxymethylbilane synthase does not house any cosynthase activity within the haem biosynthetic pathway.

Uroporphyrinogen III, the universal progenitor of macrocyclic, modified tetrapyrroles, is produced from aminolaevulinic acid (ALA) by a conserved pathway involving three enzymes: porphobilinogen synthase (PBGS), hydroxymethylbilane synthase (HmbS) and uroporphyrinogen III synthase (UroS). The gene encoding uroporphyrinogen III synthase has not yet been identified in , but it has been suggested that this activity is housed inside a bifunctional hybroxymethylbilane synthase (HmbS). Additionally, an unknown protein encoded by PF3D7_1247600 has also been predicted to possess UroS activity.

Calculating metalation in cells reveals CobW acquires Co for vitamin B biosynthesis while related proteins prefer Zn.

Protein metal-occupancy (metalation) in vivo has been elusive. To address this challenge, the available free energies of metals have recently been determined from the responses of metal sensors. Here, we use these free energy values to develop a metalation-calculator which accounts for inter-metal competition and changing metal-availabilities inside cells.

The requirement for cobalt in vitamin B: A paradigm for protein metalation.

Vitamin B, cobalamin, is a cobalt-containing ring-contracted modified tetrapyrrole that represents one of the most complex small molecules made by nature. In prokaryotes it is utilised as a cofactor, coenzyme, light sensor and gene regulator yet has a restricted role in assisting only two enzymes within specific eukaryotes including mammals. This deployment disparity is reflected in another unique attribute of vitamin B in that its biosynthesis is limited to only certain prokaryotes, with synthesisers pivotal in establishing mutualistic microbial communities.

Replacement of the Cobalt Center of Vitamin B by Nickel: Nibalamin and Nibyric Acid Prepared from Metal-Free B Ligands Hydrogenobalamin and Hydrogenobyric Acid.

The (formal) replacement of Co in cobalamin (Cbl) by Ni generates nibalamin (Nibl), a new transition-metal analogue of vitamin B . Described here is Nibl, synthesized by incorporation of a Ni ion into the metal-free B  ligand hydrogenobalamin (Hbl), itself prepared from hydrogenobyric acid (Hby). The related Ni  corrin nibyric acid (Niby) was similarly synthesized from Hby, the metal-free cobyric acid ligand.

Zinc Substitution of Cobalt in Vitamin B : Zincobyric acid and Zincobalamin as Luminescent Structural B -Mimics.

Replacing the central cobalt ion of vitamin B by other metals has been a long-held aspiration within the B -field. Herein, we describe the synthesis from hydrogenobyric acid of zincobyric acid (Znby) and zincobalamin (Znbl), the Zn-analogues of the natural cobalt-corrins cobyric acid and vitamin B , respectively. The solution structures of Znby and Znbl were studied by NMR-spectroscopy.

The Hydrogenobyric Acid Structure Reveals the Corrin Ligand as an Entatic State Module Empowering B Cofactors for Catalysis.

The B cofactors instill a natural curiosity regarding the primordial selection and evolution of their corrin ligand. Surprisingly, this important natural macrocycle has evaded molecular scrutiny, and its specific role in predisposing the incarcerated cobalt ion for organometallic catalysis has remained obscure. Herein, we report the biosynthesis of the cobalt-free B corrin moiety, hydrogenobyric acid (Hby), a compound crafted through pathway redesign.

Chester treadmill police tests as alternatives to 15-m shuttle running.

Background: Police officers require a specific level of aerobic fitness to allow them to complete personal safety training and specialist roles. Officers' aerobic fitness is assessed using the 15-m multi-stage fitness test (MSFT); however, due to the agility required and risk of injury, two alternative treadmill tests have been designed to predict four of the key minimum VO2 criteria of 35, 41, 46 and 51 ml·kg-1·min-1.

Aims: To investigate the validity and reliability of Chester Treadmill Police Walk Test (CTPWT) and Chester Treadmill Police Run Test (CTPRT).

Bacterial sensors define intracellular free energies for correct enzyme metalation.

There is a challenge for metalloenzymes to acquire their correct metals because some inorganic elements form more stable complexes with proteins than do others. These preferences can be overcome provided some metals are more available than others. However, while the total amount of cellular metal can be readily measured, the available levels of each metal have been more difficult to define.

Construction of Fluorescent Analogs to Follow the Uptake and Distribution of Cobalamin (Vitamin B) in Bacteria, Worms, and Plants.

Vitamin B is made by only certain prokaryotes yet is required by a number of eukaryotes such as mammals, fish, birds, worms, and Protista, including algae. There is still much to learn about how this nutrient is trafficked across the domains of life. Herein, we describe ways to make a number of different corrin analogs with fluorescent groups attached to the main tetrapyrrole-derived ring.

Human Intrinsic Factor Expression for Bioavailable Vitamin B Enrichment in Microalgae.

Dietary supplements and functional foods are becoming increasingly popular complements to regular diets. A recurring ingredient is the essential cofactor vitamin B (B). Microalgae are making their way into the dietary supplement and functional food market but do not produce B, and their B content is very variable.

Elucidation of the biosynthesis of the methane catalyst coenzyme F.

Methane biogenesis in methanogens is mediated by methyl-coenzyme M reductase, an enzyme that is also responsible for the utilization of methane through anaerobic methane oxidation. The enzyme uses an ancillary factor called coenzyme F, a nickel-containing modified tetrapyrrole that promotes catalysis through a methyl radical/Ni(ii)-thiolate intermediate. However, it is unclear how coenzyme F is synthesized from the common primogenitor uroporphyrinogen iii, incorporating 11 steric centres into the macrocycle, although the pathway must involve chelation, amidation, macrocyclic ring reduction, lactamization and carbocyclic ring formation.

Effect of bio-engineering on size, shape, composition and rigidity of bacterial microcompartments.

Bacterial microcompartments (BMCs) are proteinaceous organelles that are found in a broad range of bacteria and are composed of an outer shell that encases an enzyme cargo representing a specific metabolic process. The outer shell is made from a number of different proteins that form hexameric and pentameric tiles, which interact to allow the formation of a polyhedral edifice. We have previously shown that the Citrobacter freundii BMC associated with 1,2-propanediol utilization can be transferred into Escherichia coli to generate a recombinant BMC and that empty BMCs can be formed from just the shell proteins alone.

Total Synthesis, Structure, and Biological Activity of Adenosylrhodibalamin, the Non-Natural Rhodium Homologue of Coenzyme B12.

B12 is unique among the vitamins as it is biosynthesized only by certain prokaryotes. The complexity of its synthesis relates to its distinctive cobalt corrin structure, which is essential for B12 biochemistry and renders coenzyme B12 (AdoCbl) so intriguingly suitable for enzymatic radical reactions. However, why is cobalt so fit for its role in B12 -dependent enzymes? To address this question, we considered the substitution of cobalt in AdoCbl with rhodium to generate the rhodium analogue 5'-deoxy-5'-adenosylrhodibalamin (AdoRbl).

Crystal structure of CobK reveals strand-swapping between Rossmann-fold domains and molecular basis of the reduced precorrin product trap.

CobK catalyzes the essential reduction of the precorrin ring in the cobalamin biosynthetic pathway. The crystal structure of CobK reveals that the enzyme, despite not having the signature sequence, comprises two Rossmann fold domains which bind coenzyme and substrate respectively. The two parallel β-sheets have swapped their last β-strands giving a novel sheet topology which is an interesting variation on the Rossmann-fold.

The structure, function and properties of sirohaem decarboxylase--an enzyme with structural homology to a transcription factor family that is part of the alternative haem biosynthesis pathway.

Some bacteria and archaea synthesize haem by an alternative pathway, which involves the sequestration of sirohaem as a metabolic intermediate rather than as a prosthetic group. Along this pathway the two acetic acid side-chains attached to C12 and C18 are decarboxylated by sirohaem decarboxylase, a heterodimeric enzyme composed of AhbA and AhbB, to give didecarboxysirohaem. Further modifications catalysed by two related radical SAM enzymes, AhbC and AhbD, transform didecarboxysirohaem into Fe-coproporphyrin III and haem respectively.